As the number and type of multimedia applications for personal computers (PC) continues to expand, both the need to and the capability to view television signals derived from broadcast, cable or video cassette signals in a window on the screen of a PC are becoming increasingly common place. Present F.C.C. rules and regulations require that all new television broadcast receivers having picture screens 13 inches or larger must be capable of displaying closed caption information. In a conventional TV set, closed caption information is decoded from the broadcast video signal and made ready for display on the bottom of the screen by use of dedicated video processors built into the television hardware.
There are no comparable F.C.C. rules and regulations pertaining to the display of closed caption information on PC monitors, nor are there any accepted industry-wide methods of capturing and displaying such information in a PC system.
While the same video processing hardware used in conventional television sets may be incorporated into PC monitors to display closed caption information on the monitor screen, there are several defects with this approach. Principally, using the same video processor hardware as conventional television sets will increase the complexity and cost of PC systems. This is particularly detrimental in view of recent trends in the PC market, which has seen a great drop in the price of PC systems, including monitors, as a result of greatly increased price competition. A second major drawback to using conventional television video processors to capture and display closed caption television on PC monitors results from the display of a TV or video quality picture in a windowing environment on a PC. While F.C.C. rules and regulations are adequate for displaying closed caption information in a minimize size font and in a dedicated location on picture screens 13 inches or larger, the window on a PC screen in which a video picture is displayed may in fact be quite small, for example less than four inches wide. While the television picture might be adequate for viewing in a PC window, the closed caption information is likely to be so small as to be unreadable.
There is therefore a need for systems and methods which can decode and display closed caption information on a computer in a windowing environment using the already existing video capture hardware resident in most PC systems.
There is a still further need for systems and methods of displaying closed caption information on a PC monitor without requiring application specific closed caption hardware.
There is a still further need for systems and methods that can decode, process and display closed caption information captured from a television signal on the monitor of a PC in an easily readable font size and format, regardless of the size and location of the window in which the video picture is displayed.